1. Field of the Invention
This invention relates to a knife blade for use in a commercial food slicing machine.
2. Related Art
This invention is a knife blade for use in a commercial slicing machine used to cut food products of the type described in U.S. Pat. No. 5,343,623 granted Sep. 6, 1994. FIG. 2 of the drawings of this description shows such a prior art knife blade 10 formed of a sheet metal stock and having apertures 12 at opposed end areas 14 of the blade. As described in the aforesaid U.S. Pat. No. 5,343,623, the blade includes a forward facing linear cutting edge 16 (the side that faces oncoming food products to be sliced) that extends parallel with a rear edge 18 over a portion of the length of the blade, the cutting edge 16 extending along an imaginary line connecting the center lines of apertures 12. The cutting edge 16 terminates at it""s opposed ends at a wider area 20 of the blade 10 and the end areas 14 correspond with the full width of the generally rectangular blade 10. The end areas 14 are rigidly clamped in a blade holder as described in the aforesaid U.S. Pat. No. 5,343,623, such holder including transverse bolts (not shown) that extend through apertures 12 and, in cooperation with the clamping device, retain multiple identical knife blades 10 spaced adjacent and parallel to each other to cut food products into slices or strip shapes. Substantial tension is applied to the blade 10 through the clamping arrangement that secures the blades at their opposed end areas but more of the tension is actually applied through the apertures 12 via the transverse mounting bolts associated with the clamping device, all as described in the aforesaid U.S. Pat. No. 5,343,623.
The location of the cutting edge 16 along a line (or a transverse plane) connecting the center lines of the apertures 12 provided a distinct advantage in accordance with this prior art knife blade configuration due to the fact that the principal tension asserted on the blade was applied through the side walls of the apertures 12. The alignment of the cutting edge 16 with the centerlines of the apertures 12 placed the tension in the transverse plane including the cutting edge 16 which at the time the prior art invention was made was considered to be advantageous, for reasons described in U.S. Pat. No. 5,343,623.
Another prior art knife blade 22 suitable for use in a blade holder of the type described in U.S. Pat. No. 5,343,623 is shown in FIG. 1. This blade is described in U.S. Design Pat. No. 392,841 granted Mar. 31, 1998. The blade 22 is utilized in a hydraulic food cutter and is mounted in a holder generally similar to that described in U.S. Pat. No. 5,343,623. This blade is formed with a cutting edge 24 on the front edge 25 that is defined by an arc of a circle having a radius R1. The concave arc of the cutting edge extends into the blade width approximately up to an imaginary line 26 that tangentially approaches the outer diameters of apertures 28 located most closely adjacent the front edge of the blade and through which mounting bolts extend when the blade is mounted in a holder.
While the knife blades in accordance with the prior art functioned for their intended purposes, it is believed that the performance of such knife blades can be improved by using a better configuration of a cutting edge of the blades.
This invention is constituted of a thin, planar generally rectangular knife blade constructed of sheet stock such as stainless steel including end areas each having a single fastener receiving aperture therein and configured to be clamped in a knife blade holder with other similar knife blades located adjacent to and extending parallel with each other to form a cutting array of knife blades.
The unique feature of the blade is the shape of the cutting edge at the front edge of the blade, namely a central circular concave curved portion terminating at tangentially extending opposed linear sections extending from opposite sides of the circular portion along the front edge of the blade up to the end areas thereof, where they intersect blade front edge portions extending (in this example) parallel with a line joining the center line of the apertures. The linear portions preferably extend up to a region where the blade end area is clamped in a holder.
The cutting edge of the blade is designed to simulate a tensioned wire supported at opposed ends at the blade clamping areas that is subjected to a transverse impact mid-length of the wire, which results in a knife blade that is remarkably stable during cutting of food products, particularly hard products, such as carrots and potatoes, and produces excellent slices of such products.